The recent literature discloses a variety of mercaptoacyl amino acids which are useful for inhibiting the conversion of angiotensin I to angiotensin II in mammals, and are, therefore, useful in the treatment of hypertension.
U.S. Pat. No. 4,105,776, issued Aug. 8, 1979 discloses mercaptoacyl amino acids wherein the amino acid is, inter alia, proline, 4-hydroxyproline and 4-alkylproline.
U.S. Pat. No. 4,154,935, issued May 15, 1979 discloses mercaptoacyl amino acids wherein the amino acid is, inter alia, 4-halogen substituted proline, or 4,4-dihalogen substituted proline.